Ma Xing-kun (马兴坤)a, Chen Hong (陈宏)a, He Yuan-jin (何元金)a, Y. Nagashimab, H. Saitob, T. Hyodob
a Department of Physics, Tsinghua University, Beijing 100084, China; b Institute of Physics, College of Arts and Sciences, University of Tokyo, Komaba, Meguro, Tokyo 153, Japan
Abstract Positron lifetime spectra have been measured in two kinds of carbon nanotube powders as a function of temperature range between 32 and 296 K. It has been found that all spectra are essentially temperature-independent in the above temperature range. The results of analysis show that there are three components in the powders of carbon nanotube with an average diameter of 30 nm, and four components in the powders of carbon nanotube with typical diameters of around 15 nm. The average values of lifetime components obtained at various temperatures are about 220, 390 ps, and 2.0 ns for the former, and about 140, 300, 650 ps and 6.4 ns for the latter.
Received: 13 April 1999
Accepted manuscript online:
(Structure of nanocrystals and nanoparticles ("colloidal" quantum dots but not gate-isolated embedded quantum dots))
Cite this article:
Ma Xing-kun (马兴坤), Chen Hong (陈宏), He Yuan-jin (何元金), Y. Nagashima, H. Saito, T. Hyodo POSITRON ANNIHILATION IN CARBON NANOTUBE POWDERS 1999 Acta Physica Sinica (Overseas Edition) 8 783
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